Drill presses are one of the oldest, and still most often used machine tool. The level of productivity of a drill press is usually taken for granted. Most operators are aware that a power feed on a drill press could increase its productivity and reduce operator fatigue, yet few drill presses have power feeds. Old design power feeds have been found to be difficult to mount and hard to set up and often if an operator wished to use the drill press manually, the power feed must be removed. Further, many of the old design power feeds do not "feel" the work so that if a drill gets dull or loaded with chips, the power feed contiues to feed, often resulting in drill breakage. Further, a primary concern of many operators is that old design power feeds are extremely expensive.
The following patents illustrate various types of patented power feeds for drill presses:
U.S. Pat. No. 2,539,468, A. E. PIHL, et al;
U.S. Pat. No. 2,579,459, R. H. ALLEN;
U.S. Pat. No. 2,807,176, W. C. BUTCHER et al;
U.S. Pat. No. 2,882,761, R. N. KNOSP et al;
U.S. Pat. No. 2,978,872, C. F. CURRAN, Jr. et al;
U.S. Pat. No. 3,129,613, J. L. BURG;
U.S. Pat. No. 3,523,470, C. S. MILLER